1. Field of the Invention
The present invention relates to a method for producing a skin-covered foamed molded article having a polystyrene resin foam layer covered with a polystyrene resin skin, and, more particularly, to a method for producing a skin-covered foamed molded article including forming a parison in a molten or softened state, blow molding the parison into a skin defining a hollow interior space, filling expanded polystyrene beads in the hollow interior space, and heating the expanded polystyrene beads filled in the hollow interior space to fuse-bond the expanded polystyrene beads to each other and to form a foam layer fuse-bonded to the skin. The present invention is also directed to a skin-covered foamed molded article.
2. Description of Prior Art
A skin-covered foamed molded article is heretofore known which is produced by placing a resin parison extruded from a die between mold halves and blow molding the parison into a skin defining a hollow interior space, filling expanded resin beads in the hollow interior space, and supplying a heating medium, such as steam, into the skin to cause the expanded polystyrene beads to expand (secondary expansion) and fuse-bond to each other.
Such a skin-covered foamed molded article not only has a good appearance provided by the skin and high thermal insulation properties derived from the foam layer of the expanded beads but also is excellent in mechanical properties, such as bending rigidity and bending strength, in spite of being light in weight because the hollow interior space of the skin is filled with the foam layer. In addition, the mechanical properties of the entire skin-covered foamed molded article can be further improved by firmly fuse-bonding the expanded beads to each other and the resulting foam layer to the skin.
A method for firmly fuse-bonding a foam layer to a skin is disclosed in JP-A-H6-339979. Specifically, disclosed is a method for producing a skin-covered foamed article including filling the hollow interior space of a skin, formed by blow molding, with pre-expanded thermoplastic resin beads before the skin cools and solidifies, and heating the beads to fuse-bond the beads to each other and to form a foam layer. According to this method, the heat remaining in the skin can be used to firmly fuse-bond the foam layer to the skin.